Pulverizing mill



March H2, i929.

J. MEAD, JR

PULVERI Z ING MLL Filed Sept. 29, 1926 4 Sheets-Sheet l v Snom/Moz March l2, E929. 1 MEAD, JR 1,704,757

PULVERIZFNG MILL Filed Sept. 29, 1926 4 Sheets-Sheet 2 uoz 149,13

J/ //////////a 7i/5W /Vf/W March 12, i929. J. MEAD, JR fj? PULV-ERIZING MILL Filed sept. 29, 1926 4 sheets-sheet 5 A J l\\\\\\\ S14/vanto@ Mgg@ March 12, E929. J. MEAD, JR

l PULVERIZING MILL Filed Sept. 29, 1926 4 Sheets--Sheel 4 A TTORNEY.

lPatented Mar. 12, 1929. y

JOHN MEAD, JYR., 0F

APATEISJT oFF Ica.

DETROIT, MICHIGAN.

rULvEBTzTNG MILL.

Application led September This invention relates to pulverizing mills vand the object of the invention is to provide a mill for pulverizing material by beattAnother object of the invention is to provide screens against which the material is beaten, the screens being formed of tool steel and being provided with faces having a multiplicity of pyramidal points providing cutting edges by which the material 1s pulverized.

Another object of the invention is to provide a pulverizing mill of the character described in which one or more of thev screens are provided with perforations through the pyramidal points and through whlch the material may pass after pulverization.

A further object of the invention is to provide a pulverizing mill in which the screens may be readily removed for cleaning or replacing and in which screens of coarser or finer quality may be readily inserted.

These objects and the several novel features of the invention are hereinafter more fully described and claimed and the preferred form of construction by which these objects are attained is shown in the accompany drawings in which- Fig. 1 is a side elevation of a pulverlzmg mill embodying my invention.

Fig. 2 is a plan view thereof.

Fig. 3 is an end elevation of the mill.

Fig. 4 is a section taken on line 4 4 of Fig. 2.

Fig. Fig. 4.

Fig. Fig. 4.

Fig. 7 is a perspective view of the crosscut blank screen for the pulverizer.

Fig. 8 is a perspective view of the crosscut perforated' screen.

Fig. 9 is a section through the cross-cut blank screen.

Fig. 10 is a section through the cross-cut 'perforated screen.

5 is a section taken on line 5 5 of 6 is a section taken on line 6,-6 of The device as shown in Fig. 1 comprises a housing formed in two halves, a lower half 1 and an upper half 2. The housing part 2 as shown in Fig. 3 is provided with an offset inlet 3, having a chute 4 leading thereinto. This inlet 3 as shown in Fig. 4 leads into a chamber 5 in the pulverizer. Within the chamber 5 is a semi-circular flange 6 formed integrally with the lower half 1 of 29, 1926. Serial No. 138,401.

the housing. This fiange 6 as shown in Figs. 4.and 5 is corrugated on both sides. A semivclrcular flange 7 is provided inthe lower half o'f the housing and a similar semi-circular flange 8 is formed in the' upper half of the housing, the two flanges 7 and 8 forming a complete circle as shown in Fig. 5. These flanges are corrugated on the inner side as shown. A shaft 9 is provided which is rotatably mounted in the bearings 10 and 11 supported on the lower half of the housing and a pulley 12 is provided for driving the shaft. A disc 13 is secured to the shaft 9 within the housing and is positioned close to the edges of the flanges 7 and 8 as shown in Fig. 4. This divides the housing into two chambers 5 and 14. As shown in Fig. 5 a series of beaters 15 are provided which are secured to the disc 13 as shown in Fig. 4 and are adapted to pass through the space between the semi-circular flange, 6 and the flanges 7 and 8. These beaters are each provided with outwardly extending ends 16. Similar beaters 17are secured near the center of the dise 13 and during rotation of the disc pass over the inner face of the corrugated liange 6. The lianges 7 and 8 are provided with an annular groove 18 and the adjacent part of the housing halves 1 and 2 are provided with an annular groove 19. These annular grooves provide ways in which blank and perforated screens may be positioned.- These screens are' each formed in a ninety degree arc and four of these screens form a complete circle. The crosscut blank screen shown in Fig. 7 is milledto provide pyramid points 20 and anges 21 are secured to the opposite sides of the blank screen and are adapted tol fit in the annular ways 18 and 19, the screen preferably being secured in position in the ways by means of set screws. The cross-cut perforated screen is shown in Fig. 8 and is exactly similar to the screen shown in Fig. 7 except that perforations 22 are provided opening through the top of each pyramid. These pyramids provide a multiplicity of cutting edges. These screens are made of tool steel and three blank screens and one perforated screen may be utilized to form a complete circle or two of each kind may be used. I have shown three cross-cut blank screens and one perforated screen in the drawing as this is the usual arrangement in which they are used, the perforated screen preferably being ,f positioned inthe lower part of the housing.

As shown in Figs. 4 and 6 a series of beaters are secured to the outer edge ofthe disc 13 and travel through the chamber 14 adjacent the faces of the blank and vperforated screens. A discharge aperture 24 is provided in the bottom of the housing 1 through which the pulverized material may pass into a bin or other suitablel receptacle;

i material and throw it against the corrugated faces of the flanges 6, 7 and 8. In this chamber 5 the material is broken up sufliciently fine to pass between the edges of the flanges 6, 7 and 8 and the edge of the ydisc 13 into the chamber 14. At this time the beaters 23 pick up the material and throw it against the cross-cut faces of the crosscut blank and perforated screens. Due to the multiplicity of sharp edges on these screens the material is reduced to a fine state and the finer material passes through the perforations lin theM perforated. screen 25. These perforations discharge into the lower part 1 of the housing and the material falls through the discharge aperture 24 into a bin or other suitable receptacle. fIhe upper half 2 of the housing is hinged to the lower half 1 at 26 and this upper half 2 may be readily turned upwardly -on the hinge 26 to allow access to the interior of the mill and when in this position the screens may be readily removed for replacement with finer or coarser screens as desired. In order to obtain extreme ineness the perforated screen may be replaced with a.bar screen having very fine openings between the bars, the bars being preferably diamond shape in cross-section to provide cutting edges.

From the foregoing description it becomes evident that thel device is very simple and eicient in operation, will not easily get out of order, is very accessible for replacement of screens and provides a device which accomplishes the objects described.l

Having thus, fully described my invention, its utilit and mode of operation what I claim an desire to 'secure by Letters Patent of the United States is 1. In a pulverizing mill, a housing adapted to receive material to be pulverized, a series of rotatable beaters within the housing, the housing being provided with a pair of annular grooves, a series of arcuate screens positioned in end to end relation in the annular'grooves and forming a complete circle about the beaters, the inner surfaces of the screens being formed to provide a series of pyramidal points, one or more of the screens being provided with perforations through the pyramidal points. v S

2. In a pulverizing mill, a housing adapted to receive materia-l to be pulverized, a series of rotatable beaters within the housing, a seriesof screens arranged about the beaters against which material is adapted to be thrown by the beaters, the screens being each formed on the surface to provide a multiplicity of pyramidal points, at least one of the screens being provided with perforations through the pyramidal points.

3. In a pulverizing mill, an arcuate screen having a multiplicity of pyramids formed on the inner surface thereof, each pyramid having an aperture through its apex opening through the outer sur ace of the screen.

4. In a pulverizing mill, a metal screen milled to provide a multiplicity of pyramidal points, each pyramid having an aperture through its apex opening through the back of the screen.

5. In a pulverizing mill, a metal screen cation.

s JOHN MEAD, JR.

Vmilled to provide a multiplicity of pyramids 

